It's unclear what the vice president was referring to. In the last presidential debate, Romney in fact defended his previous criticisms of Russia.

"I have clear eyes on this. I'm not going to wear rose-colored glasses when it comes to Russia or Mr. Putin, and I'm certainly not going to say to him, I'll give you more flexibility after the election," Romney said during that debate, referring to an open mice moment where President Obama assured Russian leaders that they could work out a missile defense program deal in a second Obama term.

A spokeswoman for Biden did not immediately respond to a request from POLITICO to clarify the vice president's comments.